From patchwork Mon May 16 19:37:13 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 573304 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3B4DDC433F5 for ; Mon, 16 May 2022 20:07:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347098AbiEPUFn (ORCPT ); Mon, 16 May 2022 16:05:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44162 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348939AbiEPT7E (ORCPT ); Mon, 16 May 2022 15:59:04 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8C1073EF10; Mon, 16 May 2022 12:53:05 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id DF12BB81613; Mon, 16 May 2022 19:53:03 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 29F6EC385AA; Mon, 16 May 2022 19:53:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1652730782; bh=wuHIDDPf5YT8eNWKePr9t1feb6qqp2dzZZGGnNQGxTU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kywtmIcqKYCpNCAJhaf2e/CCakopC2b+zOS+ZyX481zt4c8sM7SV/wdyNwEpJlGe/ ezXI32cGOpuuoDngPsxu/hfVBUS2OeBGFAdx3H4IRxZmVIqt+ukmnnE9LYWuwVjPPY aq7GvkTxRX/a62GUchfpEIQ1CGcdMcnZsNPesqjQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Felix Fu , Al Viro , Trond Myklebust , Meena Shanmugam Subject: [PATCH 5.15 099/102] SUNRPC: Ensure we flush any closed sockets before xs_xprt_free() Date: Mon, 16 May 2022 21:37:13 +0200 Message-Id: <20220516193626.843547482@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220516193623.989270214@linuxfoundation.org> References: <20220516193623.989270214@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Trond Myklebust commit f00432063db1a0db484e85193eccc6845435b80e upstream. We must ensure that all sockets are closed before we call xprt_free() and release the reference to the net namespace. The problem is that calling fput() will defer closing the socket until delayed_fput() gets called. Let's fix the situation by allowing rpciod and the transport teardown code (which runs on the system wq) to call __fput_sync(), and directly close the socket. Reported-by: Felix Fu Acked-by: Al Viro Fixes: a73881c96d73 ("SUNRPC: Fix an Oops in udp_poll()") Cc: stable@vger.kernel.org # 5.1.x: 3be232f11a3c: SUNRPC: Prevent immediate close+reconnect Cc: stable@vger.kernel.org # 5.1.x: 89f42494f92f: SUNRPC: Don't call connect() more than once on a TCP socket Cc: stable@vger.kernel.org # 5.1.x Signed-off-by: Trond Myklebust Cc: Meena Shanmugam Signed-off-by: Greg Kroah-Hartman --- fs/file_table.c | 1 + include/trace/events/sunrpc.h | 1 - net/sunrpc/xprt.c | 7 +------ net/sunrpc/xprtsock.c | 16 +++++++++++++--- 4 files changed, 15 insertions(+), 10 deletions(-) --- a/fs/file_table.c +++ b/fs/file_table.c @@ -375,6 +375,7 @@ void __fput_sync(struct file *file) } EXPORT_SYMBOL(fput); +EXPORT_SYMBOL(__fput_sync); void __init files_init(void) { --- a/include/trace/events/sunrpc.h +++ b/include/trace/events/sunrpc.h @@ -976,7 +976,6 @@ DEFINE_RPC_XPRT_LIFETIME_EVENT(connect); DEFINE_RPC_XPRT_LIFETIME_EVENT(disconnect_auto); DEFINE_RPC_XPRT_LIFETIME_EVENT(disconnect_done); DEFINE_RPC_XPRT_LIFETIME_EVENT(disconnect_force); -DEFINE_RPC_XPRT_LIFETIME_EVENT(disconnect_cleanup); DEFINE_RPC_XPRT_LIFETIME_EVENT(destroy); DECLARE_EVENT_CLASS(rpc_xprt_event, --- a/net/sunrpc/xprt.c +++ b/net/sunrpc/xprt.c @@ -929,12 +929,7 @@ void xprt_connect(struct rpc_task *task) if (!xprt_lock_write(xprt, task)) return; - if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state)) { - trace_xprt_disconnect_cleanup(xprt); - xprt->ops->close(xprt); - } - - if (!xprt_connected(xprt)) { + if (!xprt_connected(xprt) && !test_bit(XPRT_CLOSE_WAIT, &xprt->state)) { task->tk_rqstp->rq_connect_cookie = xprt->connect_cookie; rpc_sleep_on_timeout(&xprt->pending, task, NULL, xprt_request_timeout(task->tk_rqstp)); --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -880,7 +880,7 @@ static int xs_local_send_request(struct /* Close the stream if the previous transmission was incomplete */ if (xs_send_request_was_aborted(transport, req)) { - xs_close(xprt); + xprt_force_disconnect(xprt); return -ENOTCONN; } @@ -918,7 +918,7 @@ static int xs_local_send_request(struct -status); fallthrough; case -EPIPE: - xs_close(xprt); + xprt_force_disconnect(xprt); status = -ENOTCONN; } @@ -1205,6 +1205,16 @@ static void xs_reset_transport(struct so if (sk == NULL) return; + /* + * Make sure we're calling this in a context from which it is safe + * to call __fput_sync(). In practice that means rpciod and the + * system workqueue. + */ + if (!(current->flags & PF_WQ_WORKER)) { + WARN_ON_ONCE(1); + set_bit(XPRT_CLOSE_WAIT, &xprt->state); + return; + } if (atomic_read(&transport->xprt.swapper)) sk_clear_memalloc(sk); @@ -1228,7 +1238,7 @@ static void xs_reset_transport(struct so mutex_unlock(&transport->recv_mutex); trace_rpc_socket_close(xprt, sock); - fput(filp); + __fput_sync(filp); xprt_disconnect_done(xprt); }